I think Google must be working on something as if they don’t produce a new SDK that covers this then their profits from banner app revenue will plummet, although why the largest tech company in the world still hasn’t done it already this late in the game is a head scratcher.
Also app/game creation software companies such as Scirra would also benefit from producing something that allows app devs to create apps with smooth and easy to implement compliance functionality, as the vast majority of casual and hobbiest app devs implement banner ads to make an extra bit of cash (some a full-time income) and chase the dream of a breakout hit, and if the have to jump through hoops to implement banner ads they’ll go elsewhere and find software that does supply this functionality. Whichever app dev software company cracks this will see devs flocking to them and their software. It would be a massive coup if Scirra got there first ahead of, for example Buildbox.
It seems that using Unity ads will be compliant, from Unity gdpr readiness statement , https://unity3d.com/legal/gdpr
"Other ad platforms are only an SDK, meaning they only profile for the purpose of advertising. This kind of in-game advertising (without any additional purpose) requires opt-in consent as its legal basis.
Unity is SDKs, it’s plugins, and it’s the engine itself. So, Unity’s profiling is compatible with other, more legitimate interests than merely ads. Crash reports, bug fixes, enabling user-user communication, etc., are each of legitimate interest to our gamers and developers. Our profiling enables those purposes. Unity is in a unique position because our profiling is compatible to those legitimate interests."